PUBG's PC patch #21 adds training mode and new weapons

Yesterday PlayerUnknown's Battlegrounds received patch #21, which among other things brings the Training Mode we already knew about, which can now be accessed via the main lobby, hosting up to 20 players who can practice before they head into the big fight.

In Training Mode you're all dropped into a 2x2 map which will start when there are more than five players in the queue, but if there are less than five in the queue matchmaking will continue for five minutes, with the session starting if there are still less than five after another five minutes. The total play time is 30 minutes too, and players can't drop below 1 HP in this mode.

A new AR weapon has also been added called the MK47 Mutant, which can be acquired on all maps and uses 7.62mm with a 20 round capacity (an extended magazine pushes this to 30). The Mutant has two firing modes - single-shot and two-round burst - and almost all types of attachments can be used aside from stocks.

On top of that we also have the new Tukshai vehicle as well, exclusive to the Sanhok map, which is a slow three-person vehicle that "fits perfectly with Sanhok's environment".

Which is the best feature in this update?